The transformation of chemical feedstocks into industrially relevant small molecules has been a long-standing challenge that has received a significant resurgence of interest in the chemical sciences. This will enable the inexpensive preparation of a wide variety of useful products ranging from fuels to pharmaceuticals. Many inexpensive, renewable or bio-based materials, such as fatty acids originating from seed oils and their derivatives, contain at least one unit of unsaturation, providing a synthetic handle for derivatization by olefin metathesis catalysts. The production of linear alpha olefins (LAOs) from the ethenolysis of seed oil derivatives has been demonstrated. For example, catalyst Ru-4
provided ethenolysis products in 35% yield (83% selectivity) using catalyst loadings of 10 ppm (turnover number (TON)=35,000), for the ethenolysis of methyl oleate (1) to 1-decene (2) and methyl-10-undecenoate (3) (Scheme 1):
However, high catalyst loadings are needed in order to achieve good selectivity for terminal olefins, making this particular system cost-prohibitive on an industrial scale.
There exists a need for systems capable of catalyzing ethenolysis reactions with high activity and selectivity on an industrial scale.